When I was in high school, I was in a club called the Military History Society, which was really a euphemism for a wargaming club. We met in the library about once a month to fight battles from various conflicts - though the only scenario I can remember that didn't involve American soldiers was set during Operation Barbarosa - using the teacher/organizer's miniatures. Most of these were, due to the nature of his collection, horse and musket era affairs and I usually try to convince everyone to let me be a cavalry commander. I only succeeded in doing this one time, and then only because there were so few participants that even the teacher had to double as referee and general. In my crowning moment of glory, I ordered a charge into a number of disorganized blue-belly reinforcements that had just gotten off of a train, pinned them against it, and destroyed them. It was a good day.
But I didn't decide to write this post in order to wax nostalgic about playing wargames.* What I remember about those games is that the organizer almost always brought a photocopied set of rules with a number of marginal notes and house rules that anyone used to the tournament environments of post-Games Workshop wargames would balk at. It occurred to me several months ago, during one of the infamous Hill Cantons after-session-bull-sessions, that these documents must have been very much like the wargaming climate that created OD&D. The rules were more of a set of suggestions for the individual clubs, like primitive roleplaying groups, used to create their own scenarios.
Recently I've been reading a number of "old school" wargaming books - Charge! Or How to Play Wargames by Peter Young, The War Game Rules and The Wolfenbuttel War by Charles S Grant, and Napoleonic Wargaming by the original Charles Grant - as part of my ongoing imagi-nations project. One thing I have observed in them is the fact that they fully expect the rules to be modified and often say so, much like one sees in the text of OD&D. Napoleonic Wargaming is almost a set of guidelines for making a wargame than a complete game, though a "summary of the rules" section does present something that is somewhat coherent as a game.
Another thing that I noticed was the similarities between these various rules, but also their tiny differences. It is not unlike, at least to my mind, the differences between Holmes, Moldvay/Cook, and Mentzer, even if those products came at a time when D&D was designed to be much more uniform from table to table.
I say all this because I believe that if the OSR has really "won," a phrase I have seen in a strangely high number of places, it is because so many groups have returned to this model of gaming. One only has to look at the blog list over to your right to see several examples of this sort of thing in action - DMs and their groups customizing a very similar set of rules to achieve different experiences.
*Actually, I totally did, but I have another point too.